package com.xch.array;

import java.util.StringJoiner;

public class Array<E> {

    private int size;

    private E[] data;


    public Array(int capacity) {
        data = (E[]) new Object[capacity];//
        size = 0;
    }

    public Array() {
        this(10);
    }


    public int getSize() {
        return size;
    }


    public int getCapacity() {
        return data.length;
    }


    public boolean isEmpty() {
        return size == data.length;
    }

    public void add(int index, E e) {


        if (size == data.length) throw new IllegalArgumentException("Array is full");

        if (index < 0 || index > size) throw new IllegalArgumentException();
        for (int i = size - 1; i >= index; i--)
            data[i + 1] = data[i];
        data[index] = e;

        size++;
        if (size == data.length) resize(2 * data.length);
    }


    public void addLast(E e) {
        add(size, e);
    }

    public void addFirst(E e) {
        add(0, e);
    }


    @Override
    public String toString() {

        StringBuilder res = new StringBuilder();
        res.append(String.format("Array: size = %d , capacity = %d\n", size, data.length));
        StringJoiner stringJoiner = new StringJoiner(", ", "[", "]");
        for (int i = 0; i < size; i++) {
            stringJoiner.add(String.valueOf(data[i]));
        }
        res.append(stringJoiner.toString());
        return res.toString();
    }

    public E get(int index) {
        if (index < 0 || index >= size) throw new IllegalArgumentException();

        return data[index];
    }

    public E getLast() {
        return get(size - 1);
    }

    public E getFirst() {
        return get(0);
    }

    public void set(int index, E e) {

        if (index < 0 || index >= size) throw new IllegalArgumentException();

        data[index] = e;
    }

    public E remove(int index) {
        if (index < 0 || index >= size) throw new IllegalArgumentException();
        E old = data[index];
        for (int i = index + 1; i < size; i++) {
            data[i - 1] = data[i];
        }
        size--;
        if (size == data.length / 4 && data.length / 2 != 0) resize(data.length / 2);
        data[size] = null;
        return old;
    }

    public E removeFirst() {
        return remove(0);
    }

    public E removeLast() {
        return remove(size - 1);
    }

    public void removeElement(E e) {
        int index = find(e);
        if (index != -1) remove(index);
    }

    public int find(E e) {
        for (int i = 0; i < size; i++) {
            if (data[i].equals(e)) return i;
        }
        return -1;
    }

    public boolean contains(E e) {
        for (int i = 0; i < size; i++) {
            if (data[i].equals(e)) return true;
        }
        return false;
    }

    private void resize(int newCapacity) {
        E[] newData = (E[]) new Object[newCapacity];
        for (int i = 0; i < size; i++) {
            newData[i] = data[i];
        }
        data = newData;
    }


}
